利用时间—速度积分评价心肌梗死患者局部心肌收缩功能

Assessment of Regional Systolic Function in Myocardial Infarction Patients by Time Velocity Integral

目的 :利用超声时间—速度积分评价三支病变的心肌梗死患者左心室局部心肌的收缩功能。方法 :超声测量 3 0例心肌梗死 (心肌梗死组 )患者和 3 0例无心脏疾患的人 (对照组 )不同壁的不同节段 (瓣环、基底段、中间段、心尖段 )的最大时间—速度积分 (TVImax)和各二尖瓣环最大下移距离 (D)。结果 :心肌梗死组患者各节段TVImax和各二尖瓣环最大下移距离均较对照组明显减低 ;有的节段时间—速度积分曲线出现双峰 ,提示收缩后收缩。心肌梗死组各二尖瓣环平均TVImax、最大下移距离与左心室射血分数相关系数分别为r =0 66、0 63 ,P均 <0 0 0 1;TVImax和最大下移距离的相关系数为r =0 83 ,P <0 0 0 1。结论 :三支病变的心肌梗死患者局部收缩功能明显减低 。

Objective: We measured various parameters with quantitative tissue velocity imaging(QTVI)to assess systolic function in regional myocardium of myocardial infarction patients with three vessels lesions. Methods: Left ventricular regional myocardium of 30 myocardial infarction patients (MI group) and 30 non-cardiac disease persons (control group) were assessed by QTVI.Dynamic images were collected and information was analyzed off-line.Left ventricular myocardial time velocity integral profiles were acquired along long axis asynchronously in mitral annular, basal, mid and apical segments of different walls. Maximum time velocity integrals (TVI max)in regional myocardium were measured. Furthermore, we measured mitral annular displacement(D)of 6 mitral annular sites with tissue tracking. Results: Time velocity integrals in different segments of left ventricular regional myocardium and D of 6 mitral annular sites were lower in MI group than in control group, especially in infarcted segments. What's more, time velocity integrals in some segments of MI group had two wave crests, reached maximum in isovolumic relaxation phase, suggesting postsystolic shortening. The mean TVI MAX and D of 6 mitral annular sites were related to left ventricular ejection fraction(r=0.66,0.63,p<0.001);the mean TVI MAX was related to the mean D(r=0.83,p<0.001). Conclusion: Regional systolic function in AMI patients with three vessel lesions is apparently impaired. Time-velocity integral and mitral annular displacement of 6 mitral annular sites with tissue tracking are valuable, reproducible,and accurate markers in the assessment of left ventricular systolic function.